From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B868C433E0 for ; Tue, 9 Jun 2020 04:20:07 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 009722063A for ; Tue, 9 Jun 2020 04:20:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ODMkb8Qm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 009722063A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=9K5rRV+Buo27mPq+xjtFLsYikFJnZ8AtNOX/AOKniEY=; b=ODMkb8QmPfVSfm uGjO2bGArpsKla6vi884AAiYwRwwFuIxDdNVmiXhefo/8CK34c7A4PPrpzUQrd6CsVMiUgwnj670I jOVa381sQ6EYUI9zEN7zS7qbuEbwlY3Kug4Kvuv2mtm2Qx2sDD63H+eXsSQlaXT7jDm3ausRiHf0D F7c9O8EwIfIVvjw2NBtTyLsIQwSo4Os+53ktgzV5FE5zKHS9FWH87LjA8dyRtGGKxU/Yqnalo2+F+ xsluWCxUmlDEIueiq2QSFWFUBkFAm1ceVq0nYLMixnSH2jHfuZPp3y6ZhlRFCHrMPHxsdu1Zop1i+ cPhSKNL72lrFdYNmKoKQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jiVjw-0000Bm-QN; Tue, 09 Jun 2020 04:19:56 +0000 Received: from [2002:c35c:fd02::1] (helo=ZenIV.linux.org.uk) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jiVjt-0000B1-AN for linux-arm-kernel@lists.infradead.org; Tue, 09 Jun 2020 04:19:55 +0000 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.93 #3 (Red Hat Linux)) id 1jiVjf-005c4C-1Q; Tue, 09 Jun 2020 04:19:39 +0000 Date: Tue, 9 Jun 2020 05:19:39 +0100 From: Al Viro To: Nicolas Pitre Subject: Re: [PULL REQUEST v2] FDPIC ELF support for ARM Message-ID: <20200609041939.GQ23230@ZenIV.linux.org.uk> References: <20200608224725.GH1605@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200608_211953_361852_684D7063 X-CRM114-Status: UNSURE ( 9.94 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Howells , Russell King - ARM Linux admin , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jun 08, 2020 at 11:48:27PM -0400, Nicolas Pitre wrote: > I suspect riscv will end up in the same situation when they upstream > their fdpic support. FWIW, one thing that needs to be done is switching fdpic to use of regset, a-la normal elf coredumps on the same arm. I really want to kill the sodding elf_core_copy_task_fpregs(), dump_fpu(), etc. Right now that crap is used by elf coredump on alpha c6x csky h8300 m68k microblaze nds32 um unicore32 fdpic coredump on arm sh/nommu and c6x Out of those only alpha, m68k, microblaze, um and unicore32 lack regset - everything else (including all users of fdpic) have working ones. And it's not at all hard to add the damn thing to those 5 architectures, killing quite bit of code in binfmt_elf.c, as well as in arch/* Note, BTW, that fdpic coredumps on arm currently have fucked FPU for all but the main thread - arm has int dump_fpu (struct pt_regs *regs, struct user_fp *fp) { struct thread_info *thread = current_thread_info(); int used_math = thread->used_cp[1] | thread->used_cp[2]; if (used_math) memcpy(fp, &thread->fpstate.soft, sizeof (*fp)); return used_math != 0; } which obviously duplicates the contents of FP registers of the coredumping thread into the NT_PRFPREG section for each thread... _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel